For each positive real number r, define T_r to be the closed interval [-r2,r2].

That is, T_r={x∈R|-r2≤x≤r2}.

Let indexing set = {m ∈ natural numbers |1≤m≤10}

Use either interval notation or set builder notation to specify each of the following sets:

⋃_(r∈R (+)) Tr

⋂_(r∈R (+)) Tr

⋃_(k∈natural numbers) Tk

⋂_(k∈natural numbers) Tk

The uppercase U is union, and upside down U is intersect. the Tr and Tk are supposed to be next to the symbol and the things in parenthesis are supposed to be below the symbol. I have no idea how to do these for problems can anyone help?